| Title: | The multispanning membrane protein Ste24p catalyzes CAAX proteolysis and NH2-terminal processing of the yeast a-factor precursor |
| Author(s): | Tam A; Schmidt WK; Michaelis S; |
| Address: | "Department of Cell Biology and Anatomy, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA" |
| ISSN/ISBN: | 0021-9258 (Print) 0021-9258 (Linking) |
| Abstract: | "Saccharomyces cerevisiae Ste24p is a multispanning membrane protein implicated in the CAAX proteolysis step that occurs during biogenesis of the prenylated a-factor mating pheromone. Whether Ste24p acts directly as a CAAX protease or indirectly to activate a downstream protease has not yet been established. In this study, we demonstrate that purified, detergent-solubilized Ste24p directly mediates CAAX proteolysis in a zinc-dependent manner. We also show that Ste24p mediates a separate proteolytic step, the first NH(2)-terminal cleavage in a-factor maturation. These results establish that Ste24p functions both as a bona fide COOH-terminal CAAX protease and as an a-factor NH(2)-terminal protease. Importantly, this study is the first to directly demonstrate that a eukaryotic multispanning membrane protein can possess intrinsic proteolytic activity" |
| Keywords: | "Amino Acid Sequence Catalysis Detergents/pharmacology Dose-Response Relationship, Drug Endopeptidase K/metabolism Endopeptidases/metabolism Genotype Mass Spectrometry Mating Factor Membrane Proteins/*metabolism Metalloendopeptidases/*metabolism Methylatio;" |
| Notes: | "MedlineTam, A Schmidt, W K Michaelis, S eng GM 41223/GM/NIGMS NIH HHS/ Research Support, U.S. Gov't, P.H.S. 2001/10/03 J Biol Chem. 2001 Dec 14; 276(50):46798-806. doi: 10.1074/jbc.M106150200. Epub 2001 Oct 1" |
